KDE Plasma 6.x  FreeBSD 14.3 
  Wayland.

     "latest",  
/usr/local/etc/pkg/repos/FreeBSD.conf  :

   FreeBSD: {
     url: "pkg+http://pkg.FreeBSD.org/${ABI}/latest",
     mirror_type: "srv",
     signature_type: "fingerprints",
     fingerprints: "/usr/share/keys/pkg",
     enabled: yes
   }

   :

    pkg update -f
    freebsd-update

  :

   pkg install drm-kmod

     loader.conf  rc.conf:

   sysrc kld_list+=amdgpu
   sysrc dbus_enable="YES"
   sysrc seatd_enable="YES"
   sysctl net.local.stream.recvspace=65536
   sysctl net.local.stream.sendspace=65536

 KDE Plasma 6 

   pkg install seatd plasma6-plasma konsole

,        "video"  

 ,        KDE Plasma:

   #! /bin/sh
   /usr/local/bin/ck-launch-session \
      /usr/local/lib/libexec/plasma-dbus-run-session-if-needed \
      /usr/local/bin/startplasma-wayland